The Bureau of Reclamation will test whether older turbines can operate safely below an elevation of 1,035 feet, according to agency spokesman Peter Soeth. The tests will include strict limits on operating hours, continuous monitoring and frequent inspections, he said.

"The testing results will clarify the shutdown elevation and provide Reclamation a more accurate picture of the facility's capacity as reservoir levels decline," Soeth said.

The stakes are visible inside the dam itself. Turbine A8, one of only five wide-head units designed to function at low water levels without guaranteed permanent damage, sits idle on a wooden plank covering the original terrazzo floor, awaiting repairs. The dam has 17 turbines in total.

Recent weather has provided a reprieve. Record flooding across the Colorado River Basin, driven by what scientists describe as a "Super El Niño" pattern, has lifted Lake Mead more than 2 feet since late October to an elevation of 1,039.41 feet as of Friday. Upstream, Lake Powell has risen about 20 feet since hitting a record low in September.

But water managers caution that the relief is temporary. The Bureau of Reclamation will not decide how much water to release from Lake Powell until April 2027, meaning Lake Mead could continue falling over the next year despite the added storage. Earlier projections had placed Lake Mead below 1,035 feet by the end of October.

"We are very appreciative for every drop of water that gets in the reservoir," said Colby Pellegrino, deputy general manager of the Southern Nevada Water Authority. But she warned that warming temperatures may be shifting how water reaches the basin — arriving as rain rather than snow — and that the supercharged El Niño pattern adds unpredictability.

"This is sort of a snapshot of what that could actually look like for the basin," Pellegrino said. "And I think that's somewhat terrifying for our river communities and how they adapt to that."

Elizabeth Koebele, a University of Nevada, Reno professor who studies Colorado River governance, said the public should not mistake the recent gains for a solution.

"We can be grateful for seeing our reservoirs rise a little bit," Koebele said. "But we also need to remember that isn't the end game. It isn't going to be the thing that gets the basin out of the current state that it's in."

For utilities, the tests carry direct consequences. Eric Witkoski, executive director of the Colorado River Commission of Nevada, said he was initially alarmed by the plan until he learned the details.

"Before, I was very concerned," Witkoski said. "Are you just going to run it down, pull it out and see if you damage it or not? But I walked away with a much better sense that they have ways to gauge it and watch for it and be able to shut them down."

His commission manages Nevada's share of Hoover Dam hydropower, which has historically powered communities in Lincoln County, Boulder City, Overton and elsewhere. This year the commission built a dashboard showing utilities how much power they can expect at different lake levels, and those utilities have been preparing to buy replacement power on the wholesale market, where prices can be volatile.

Witkoski described the range between 1,025 and 1,035 feet as a "gray area" where it remains unclear how much power utilities will be able to purchase during the low-level experiments.

Longer term, the Bureau of Reclamation is using funding from the federal Help Hoover Dam Act to replace at least two older turbines with wide-head models capable of operating at low levels. Soeth said the first new turbine is expected to be installed in 2028.

Witkoski welcomed the breathing room from the floods but said the underlying problem remains.

"As the water folks will tell you, we've had a drought for over 20 years, so we've got a long way to go," he said.